<div class="address-group">
  <div>
    <mat-form-field>
        <mat-select  placeholder="请输入省份" [(ngModel)]="_address.province" (selectionChange)="onProvinceChange()">
            <mat-option *ngFor="let p of provinces$|async" [value]="p.code">{{p.name}}</mat-option>
          </mat-select>
    </mat-form-field>
  </div>
  <div>
    <mat-form-field>
        <mat-select  placeholder="请输入城市" [(ngModel)]="_address.city" (selectionChange)="onCityChange()">
            <mat-option *ngFor="let c of cities$|async" [value]="c.code">{{c.name}}</mat-option>
          </mat-select>
    </mat-form-field>
   
  </div>
  <div>
      <mat-form-field>
          <mat-select placeholder="请输入区县" [(ngModel)]="_address.district" (selectionChange)="onDistrictChange()">
              <mat-option *ngFor="let d of districts$|async" [value]="d.code">{{d.name}}</mat-option>
            </mat-select>
      </mat-form-field>
   
  </div>
</div>
<div class="street">
    <mat-form-field class="example-full-width" color="primary">
      <input type="text" matInput placeholder="请输入街道地址" [(ngModel)]="_address.street" (change)="onStreetChange()" >
    </mat-form-field>
</div>